It would seem the very first thing you would do is provide an example for vanilla JS so that everyone could get started. It is impossible to use this at all for the large proportion of the world that isn't using React as we can't even see a single example.

If it's so complicated to use that it takes more than a minute of vanilla JS coding to initialize it, then I don't think I'm interested, thanks all the same.

They use it internally, why would they rebuild it in vanilla before they released it? Sounds like they are working on it even though it's of no use to them.